Electrical line clamp



United States Patent ELECTRICAL LINE CLAMP Everette Lamb, Tyler, Tex. Application September 6, 1955, Serial No. 532,684

Claims. (Cl. 339-246) This invention relates to electrical line clamps and more particularly to electrical line clamps of the parallel groove type suitable for hot line work.

lt is an object of this invention to provide an electrical line clamp adapted to clamp two wires, one of which may be hot, in a safe and foolproof manner.

It is a further object of this invention to provide a clamp which can be easily assembled and when once assembled cannot be improperly connected to conductors.

lt is another object to provide an arc proof clamp for hot lines.

It is yet another object to provide a clamp having an upper cap, a center spacer and a bottom plate, with means for assemblying and bringing together these elements so that two electrical conductors may be clamped thereby.

The above and other objects will appear more clearly from the following detailed description and drawing, showing, by way of example, a preferred embodiment, and wherein:

Fig. l is an exploded perspective View of the clamp members;

Fig. 2 is an end elevation showing the clamp members prior to assembly with electrical conductors; and

Fig. 3 is a side elevation showing the clamp in assembled position and showing the upper cap in dotted lines as it would be positioned prior to connecting it with electrical conductors. 4

As shown in the various gures of the drawing, the clamp 1t) comprises a bottom plate 12, a center spacer 14 and an upper cap 16 each being apertured and mounted on a bolt 18 which is headed at one end and threaded on the other to receive a suitable nut. A coil spring 20 fits over the bolt between the bottom plate 12 and the center spacer 14.

The bottom plate 12 has a longitudinal conductor seat 22 adjacent one end of the upper face of the plate. Adjacent this seat 22 are a pair of upstanding side walls 23 terminating in ears 24 which are perpendicular to the conductor seat and extend above same. Aligned vertical abutments 26 are formed by the ends of the walls 23 and are generally perpendicular to the plate face portion 28 which constitutes the upper face of the other end of the plate opposite that having the conductor seat. This plate face portion 2S is somewhat lower than the conductor groove 22 and extends between walls 23 to provide a recess into which coil spring 20 fits as will be explained later. The bottom 32 of the plate is generally flat, particularly where it bears against the bolt head.

The center spacer 14 has a longitudinal conductor seat 34 on its lower face 36 adjacent one end. A projection 38 extends longitudinally on the upper face 40 of the spacer adjacent the end having the downward facing conductor seat and has a plane face 42 perpendicular to face 40. This face 42 is directed toward the other end of the spacer. The projection 38 has a flat top face 43. The spacer has a longitudinal conductor seat 44 in its upper face adjacent the opposite end. The spacer 14 has rectangular cut out portions 46 spaced to be received beice tween bottom plate ears 24, as indicated in Figs. l and 3.

The upper cap 16 has a longitudinal conductor seat 50 channeled in its smooth flat lower face 52 adjacent one end thereof. The end of the cap opposite to that having the conductor seat is a plane vertical surface 54 which is adapted to cooperate with projection face 42 of the spacer as will be explained later. The upper face has two upwardly projecting members 56 having inner faces adapted to engage the sides of a nut used in the assembling of the clamp.

The bottom plate, center spacer, and upper cap have aligned holes 60, 62 and 64 respectively which are adapted to receive the bolt 18. As shown in Figs. 2 and 3, the clamp is assembled by first placing a lock washer 66 over the bolt next to the head and putting the bottom plate 12 on, then the coil spring 20, next the center spacer 14, upper cap 16, and then nut 68.` In the assembled condition, conductor seat 22 faces conductor seat 34 in the spacer and conductor seat 44 faces seat 5t) in the upper cap. The recesses 46 in the spacer. allow this member to fit down between the ears 24 as indicated in Fig. 3. This aids in maintaining correct alignment between the bottom plate and the spacer. The abutting of surface 54 of the upper cap against face 42 of projection 38 on the center spacer serves to maintain the upper cap and spacer in alignment.

The coil spring 20 selves to maintain the clamp elements 14 and 16 in engaged position on the holt even though the nut is near the end thereof. ln other words, the unit when assembled and properly adjusted presents a reasonably stable clamp in which the elements may be moved to allow for connecting to hot and tap lines.

ln use, the clamp is assembled with the nut in the position as indicated in dotted lines in Fig. 3. The upper cap 16 is rotated 90 degrees so that its lower face 52 will bear on the top Vface 43 of spacer projection 38 as shown in dotted lines in Fig. 3. Thus coil spring 2li is compressed and the spacer 14 pressed down toward bottom plate 12. Next, the head of bolt 18 is placed in the hot stick which is capable of thus holding the clamp for full manipulation thereof. Then the conductor seat S0 in the upper cap is seated on the main (hot) conductor 70 and the bolt 18 rotated 90 degrees. The conductor holds the cap fixed and friction between the bolt and bottom plate rotates the latter and with it the spacer, thereby bringing the conductor seat 44 into alignment with seat 50 and under urging from spring 20 the spacer will be forced upward so that seats 50 and 44 will engage and grip the conductor 70. The raising of the spacer 14 leaves a gap between the conductor seats 22 and 34 which are used for holding the tap wire 72. This gap makes it possible to insert the tap wire 72 from the side rather than the end and thus reduces arcing to a considerable extent. After the tap wire is inserted the clamp is tightened by continued rotation of the bolt so that it will assume the arrangement shown in full lines in Fig. 3. In order to remove the clamp the above procedure is reversed.

This clamp connector cannot be incorrectly assembled or improperly installed by hand or by the use of a hot stick because each member is interitted with the other so that is not possible to operate the clamp in any but the proper manner.

This clamp may be made of various materials depending upon the particular needs of a given installation.

Having thus described my invention, what l claim as novel and desire to secure by Letters Patent of the United States is:

l. An electrical clamp particularly adapted for hot line work, said clamp comprising, an upper cap, a center spacer, a bottom plate, each of these members havinga hole adapted for alignment with the others, a headed bolt end .ef .the lewer feeeeflhe weerlegd, ed. the .eerresredding end portion of the upper Aface ofthe spacer, copperating eendueter seele termed` en ,the lowerv fece efjthe .ether end pertien efzthe Speeer and the'eelfeependdg endend upper 'face of the'plate, said bottom1 plate having Va pair 0f dpetandirlg eers., 011e O11 "eeelleide, Seid ieerebe'ng adapted to engage the'sid'es of the center spacer to maintain alignment between the ,two wmembers, said. center Speeer hevig apfeieedexl exteldirng upwerdly @delle end portion above the conductor seat` onfthe lower face thereonthe yupper cap having a f lat` lower face onuthe end rportion,"opposite the lconductor seat, said caplower face being adapted to bearon the topofthespacer projection when the'cap is rotated 9,0 degreesqtherebvy main- V taining the upperjcap yin a raised position so that a conl ductor'may be readily-positioned in lthe conductor seat in Vthe upper face ofthe spacer. p y

2. The device as describedin claim lwherein a J'coil spring is positioned on the bolt between the lower-plate and center spacer. Y t K 3. The device as described in claim 2 whereingthe'iend Yface ofthe upper cap opposite (to that adjacent the conductorl seat a plane vertical surface adapted to cooperate with the vertical face of the spacer projection to aid in retaining the crap and spacer conductor seats in alignment and wherein t'he upper cap has nut engaging means adapted to prevent the nut from rotating with respect tothe upper Cap. I t v 4. An electrical clamp particularly adapted for hot line work, said clamp'comprising an upper cap, a center 1 spacer member, a bottom'lplaite member, cooperating con- `4 f duetor seats formed on one end portion of the lower 'face of 'the "e'ap "and o'n the "corresponding end portion of the upper face of the spacer member, cooperating conductor seats formed on theiother end of the lower face of the spacer member and the corresponding end portion of the upper face of the plate member, a single vertical axis mounting means for retaining the cap, spacer member, and plate member in `assembled and vertically adjustable position, measfrihaintainng alignment of the spacer member'an'd'theplate'memberjthroughout the range of relative vertical movement thereof, and a projection extending 4vuirvar'dly'onithe end 'portion of the center Spacer. member ebreve `the, eendueter Seat. en., the lower face thereof, thecap rlower `face beigadapted `t bear on the top of the "spacer vprojection when the cap is rotated thereby maintaining the upper cap in raised position so that a conductor may be readily positioned in the conductor seat in the upper face of the spacer member. v L

Y5 Theideviee as described in Claim 4, Whereintheteep, spacer member and plate member "eachphave ahole which is in alignment vwith `the holes inthe otherumembers so thatthern'ounting means may vextend therethroughuto maintain fheelamp. in assembled and vertieelly adjustable position and wherein thel spacer member has means engaging the capito align the spacer and cap.

France Ian. '18, 1950 

